Set family operations #
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This file defines a few binary operations on set α
for use in set family combinatorics.
Main declarations #
s ⊻ t
: Set of elements of the forma ⊔ b
wherea ∈ s
,b ∈ t
.s ⊼ t
: Set of elements of the forma ⊓ b
wherea ∈ s
,b ∈ t
.
Notation #
We define the following notation in locale set_family
:
s ⊻ t
s ⊼ t
References #
@[protected]
s ⊻ t
is the set of elements of the form a ⊔ b
where a ∈ s
, b ∈ t
.
Equations
@[simp]
@[simp]
@[simp]
theorem
set.image_sup_prod
{α : Type u_1}
[semilattice_sup α]
(s t : set α) :
function.uncurry has_sup.sup '' s ×ˢ t = s ⊻ t
@[protected]
s ⊼ t
is the set of elements of the form a ⊓ b
where a ∈ s
, b ∈ t
.
Equations
@[simp]
@[simp]
@[simp]
theorem
set.image_inf_prod
{α : Type u_1}
[semilattice_inf α]
(s t : set α) :
function.uncurry has_inf.inf '' s ×ˢ t = s ⊼ t
@[simp]
theorem
upper_closure_sups
{α : Type u_1}
[semilattice_sup α]
(s t : set α) :
upper_closure (s ⊻ t) = upper_closure s ⊔ upper_closure t
@[simp]
theorem
lower_closure_infs
{α : Type u_1}
[semilattice_inf α]
(s t : set α) :
lower_closure (s ⊼ t) = lower_closure s ⊓ lower_closure t